1. Field of the Invention
The present invention relates generally to a method and apparatus to induce sound sleep and waking, and, more particularly, to a method and apparatus to induce sound sleep and waking, which measure physiological signals using a non-contact type sensor which does not contact the body of a user, and, when variation in the measured physiological signals occurs, re-adjusts the sleep environment by changing a sound sleep and waking inducing protocol, thereby enabling the feedback control of the sleep environment.
2. Description of the Related Art
Due to the complicated lifestyle in modern societies and the influence between the members of the societies, modern people are subject to a lot of stress. Because of the stress, they do not have sufficient sleep, which undesirably affects their bodies. Therefore, in order to induce comfortable and agreeable sleep, a number of technologies have been proposed.
Korean Unexamined Patent Publication No. 2003-0032529 discloses a device and method to induce sleep, which output vibrations and/or ultrasound waves in a frequency band, which was determined in repeated studies, depending on the body state of a user while collecting physiological information about the user, thereby optimally inducing sleep.
Furthermore, Japanese Unexamined Patent Publication No. 2003-260040 discloses a sleeping depth estimation device that includes a vital information sensor detecting vital information including the heart rate and breathing rate of a human body, a vital information processing circuit calculating a plurality of pieces of basic data about sleep depth through the processing of the vital information detected by the vital information sensor, and a sleep depth estimating circuit estimating the sleep depth based on the basic data obtained by the vital information processing circuit.
However, the related art technologies have problems in that a sensor detecting the sleep state of a user is not used, or, even if a sensor is used, the sensor contacts the body of the user, so that a user, who is trying to fall asleep, feels uncomfortable. Furthermore, there is a problem in that it is hard to simultaneously detect variation in the physiological signals of a sleeping user and variation in the sleep environment, and perform feedback control on the sleep environment even if a non-contact type sensor is used.